B7 A4: planning some mods (exhaust, intake, ecu). Tips/ suggestions?
 

I just bought a 2007 b7 a4 2.0t. I am looking to increase performance for a resonable price, but with out doing any longterm damage to the car. I would like to invest in a catback exhaust, an intake, and an ecu. I am planning to drive this car for at least 4 or 5 years and I want it to last. Any tips/ suggestions on where i should start, and how i can protect my car from damage some of my friends have warned me about?

Thanks